Locomotive boiler firebox



March 21, 1939. 3 J c g so 2,151,009

LOCOMOTIVE BOI LER FIREBOX Filed Jan. 22, 1958 4 Sheets-Sheet l Q a a M O O 0000 a M 0 00000 N \J 5 6 March 21, 1939. G, J. CHRISTENSON LOCOMOTIVE BOILER FIREBOX Filed Jan. 22, 1938 4 SheetsSheet 2 March 21, 1939. G. J. CHRISTENSON 2,151,009

LOCOMOTIVE BOILER FIREBOX Filed Jan. 22, 1938 4 Sheets-Sheet 3 March 21, 1939. G, J. CHRISTENSON LOCOMOTIVE BOILER FIREBOX Filed Jan. 22, 1938 4 Sheets-Sheet 4 A o i I i t 1 I I I 1 I I I i I 5 1 4 t 4 Patented Mar. 21, 1939 UNITED STATES PATENT OFFICE 2,151,009 LOCOMOTIVE BOILER. FIREBOX Application January 22, 1938, Serial No. 186,332

6 Claims.

This invention relates to improvements in locomotive boiler fireboxes and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

One of the objects of the present invention is to provide a simple improved means in a firebox of this kind whereby it is possible to materially increase the heating surface of the firebox without increasing the size thereof so as to obtain a more efficient thermic transmission between the products of combustion and the boiler water and thereby establish better circulation of the boiler water as well as improving the steaming qualities of the boiler. I

Another object of the invention is to provide means which increases water circulation in the side water legs so as to keep them in a cleaner condition by removing the water from said legs and discharging the same through laterally spaced Portions of the crown sheet into the boiler water space above the same so as to assure a more positive flooding of the crown sheet under low water conditions.

A further object of the invention is to provide means of this kind, which ably supports a much better arch structure, from which brick are not so apt to fall and leave openings in the arch to disturb the intended draft action.

Again, it is .an object of the invention to provide means of this kind which divides the upper portion of the firebox into at least three longitudinal passageways for the flow of the products of combustion towardthe front end of the firebox, thus exposing more surface area of the circulat- 5 ing and steaming elements to the products of combustion for a greater thermic transmission to the water flowing through the elements.

Again, it is a further object of the invention to provide a water heating and circulating ele- 40 ment, which is simpler and less expensive to make than elements for similar purposes as heretofore devised.

Also, it is still a further object of the invention to provide a water steaming and circulating element of this kind, which is so formed as to make it practical to produce but one size of element with inlet and outlet legs and which element is so constructed that end parts of said legs may be removed to fit the element in diiferent sizes of fireboxes or' in different positions in the same firebox.

The above mentioned objects of the invention,

as well as others, together with the several advantages thereof, will more fully appear as the specification proceeds.

In the drawings:

Fig. 1 is a longitudinal vertical sectional view through a combustion chamber type of locomotive boiler firebox embodying the preferred form of the invention.

Fig. 2 is a transverse vertical sectional view through a part of the firebox appearing in Fig. 1 as taken on the line 2--2 of said Fig. 1.

Fig. 3 is a transverse vertical sectional view through the combustion chamber end of the fire- 10 box as taken on the line 3--3 of Fig. 1.

Fig. 4 is a detail horizontal sectional view through a part of the firebox as taken on the line 4-4 of Fig. 2.

Fig. 5 is a fragmentary, horizontal detail sec- 15 tional view as taken on the line 5-5 of Fig. 2.

Fig. 6 is a view similar to Fig. 4 showing a modifled form of the invention.

Fig. 7 is a longitudinal detail section through a part of one of the circulating elements and asso- 20 ciated arch brick, on an enlarged scale, as taken on the line 'l-l of Fig. 6.

Fig. 8 is a fragmentary view similar to Fig. 2 and shows a water steaming and circulating element embodying a modified form of the inven- 25 tion, a part of the element being shown in longitudinal section.

Fig. 9 is a detail vertical sectional view, on an enlarged scale, through a part of the element appearing in Fig. 8 as taken on the line 9-9 of said 30 Fig. 8.

Fig. 10 is a view in elevation of the-top end of a circulating element embodying a further modified form of the invention.

Fig. 11 is a top plan view of the parts appearing in Fig. 10.

Referring now in detail to that embodiment of the invention illustrated in Figs. 1 to 4 inclusive of the accompanying drawings, the firebox therein shown includes a crown sheet I 5 which merges into the inner side sheets IS, the inner back sheet I? and the inner throat sheet IS. The crown sheet extends forwardly of the inner throat sheet ill to form the top of the combustion chamber 19. This chamber is closed at the front end by the flue sheet 20 and the bottom 2| of said chamber merges into the front end of the inner throat sheet i8. I

The outer rear sheet of the locomotive boiler I is indicated at 22, the outer side sheets are indie cated at 23 and the outer'throat sheetj'is, indicated at 24. The said sheets justment'ioned cooperate with the top sheet and the outer side sheets 23 in forming the back water leg 25, the side water legs 26 and the front throat 21 respectively, all 5 tional in locomotive type of firebox boilers and requires no further detailed ducription other than to say that associated parts of the various sheets just mentioned are suitably staybolted in the usual manner.

To increase the effective evaporating surface ,ofthefireboxandthewatersteamingandcirculating efilciency of the associated boiler, as well astoprovides'upportforanarchinthe firebox, when such an arch is desired, I provide the following arrangement:

In the firebox I provide one or more elements each having a lower portion that has its ends opening through the side sheets and a plurality of spaced apart upper portions that connect said lower portion with the boiler water space above the crown sheet. The number of such elements is, of course, dependent upon the size and type of firebox. As shown in Fig. 1 there are four of such elements spaced apart longitudinally and extending transversely across the firebox and which elements are indicated at IHl-il and II respectively. In the combustion chamber II is a fifth and similar element 84.

Allofthesaidelementsaresimilarinstructureanddiiferonlyinsiseasmanifestedprincipally in the length of certain of the parts thereof. Therefore, a description of one element will sumce for all. Taking the rearmost element It in the firebox as an example, the same includes a hollow lower portion in the form of a pair of outwardly and downwardly extending tubular inlet legs 35-" respectively, the outer extremity of each of which opens through and is welded pressure-tight in an associated side sheet. il-

ttindicatetheupwardlyextendingtubularoub' let legs of the element, the top ends of which open through and are welded pressure-tight in the crown sheet. Preferably the outlet legs of the element are spaced apart transversely of the firebox, one on each side of the longitudinal medianline thereof and stand in the plane of the legs of the lower portion. The outlet legs Ilarespacedapartwithreferencetothespacing ofthestaysforthecrownsheetsoastohave theiraxes disposedinplanesbetweentheadiacent longitudinal rows of such stays. With such an arrangement, four of such stays are removed from operative connection with the crown sheet for each outlet leg as is evident from Fig. 5. The lower ends of the outlet legs of the element curve inwardly toward each other to connect at a Junction-like mid portion 81 with the top contral part of the lower portion. If desired. thefrontandrearwallsoftheiunction-likemid portionsmaybestayboltedasatll. Theopposed inner surfaces of the outlet legs "Join-as a crotch II that forms the top for the Junctionlike mid portionjl.

Itispointedoutatthistimethatthelm 35-" are disposed at suchvdiverging inclinations asisdesiredinthelateralinclinationofthetwo sidesofthearch,whensuchanarchistobe used in the firebox. When the inclination is such astocausetheendsofsaidlegstoapproach the associated side sheets at too acute an angle said ends may be bent slightly, as appears in Fig. 2, so as to approach said side sheets at an angle better adapted for securing said ends in said sheets as by welding.

The outlet legs, which are preferably parallel, project a short distance through the crown sheet and are welded pressure-tight from inside the firebox. As shown in Figs. 1 and 2 these legs are in the form of circular tubes and the radial stays of the boiler are cut oil! from the crown sheet and the openings for such outlet legs are so disposed as to require the cutting oil of only four radial stays for each outlet leg. Instead of the outlet extremities of said legs being circular, they may be flattened on both sides as at 360 in Figs. 10 and 11 so as to be of an elongated shape, longitudinally of the crown sheet. By arranging the outlet end of this shape, in line with a respective longitudinal row of stay bolts, only two of such bolts require removal. for each outlet end as appears in Fig. 11.

With the arrangement of the elements illll-fl and 33 in the firebox as shown in Fig. l, the element 30 has the least vertical dimension and the element 31 has a greater vertical dimension. The element 32 has a still greater vertical dimension and the element 33 has the greatest vertical dimension. In securing the ends of the inlet legs 35 of the various elements in the side sheets. suitable openings are made in the side sheets to receive said ends and these openings are laid out on an inclined line having that inclination it is desired to impart to an arch, when such an arch is to be employed in the firebox.

Thus when the various elements are in place in the firebox, it will be found that the longitudinal dimensions of both the inlet and outlet legs of the various elements increase successively toward the front end of the firebox.

In making up the elements to go into a firebox, they are all made with the greatest longitudinal dimension of the various legs, and then the legs are cut of! at such lengths as will adapt each element for its own particular place or location in the firebox. While the outlet legs "-36 of the element are shown in the drawings, as parallel, they may be made to diverge upwardly and outwardly from the Junction part I]. The parallel relation of said legs is preferred because in removing the top ends thereof for fitting the element in the firebox, the lateral spacing between said legs doesnot vary. Thus the crown sheet bolts requiring removal are kept in line. In making up an element, it is preferred that they be made from two similar patterned or counter parts each having a substantially semicylindrical cross section along any point in the legs thereof and then arrange and weld the edges of said parts in abutting relation as appears at 40 in Fig. l.

When an arch is desired in the firebox, a series of side brick ll is laid upon the various inlet legs of the elements. In this respect, it is pointed out that the ends of the brick (longitudinally of the firebox) engage at their ends upon the said inlet legs as appears in Fig. 1, suitable lugs 42 being provided on the inner throat sheet to support the front ends of the first series of brick at the front end of the firebox. Each series of brick is made up of a pair of laterally spaced sets of brick as appears in Fig. l, the innermost end bricks in each two sets being separated to provide a space substantially 'in line with the junction portions of the various elements and which space is filled in by central key brick I! having a wedge-like engagement at its sides in said space. With this arrangement the central brick 43 have no end supporting engagement, said brick merely having an end engagement with the faces of the junction portions of the elements 303i-32 and 33 between which they are disposed.

To provide an end support for such central brick, an outwardly extending hollow boss 44 may be provided on the opposed faces of the junction portions 31 of the adjacent elements. This arrangemenii with the end support for said central brick best appears in Figs. 6 and 7.

In Figs. 8 and 9 I have shown a modified form of cross sectional area for the inlet legs of each element. In this modified form, I provide an outwardly extending bulge or hollow rib 45 on opposite sides of both inlet legs and which rib is continuous of the length of said lower portion of the element. With such an arrangement, the inlet .ends may be flattened on the top and bottom, so that the sides of said ends are coincident with said hollow ribs as best appears in Fig. 9. This arrangement has its advantages not only in the provision of better end supports for the brick, but it increases the superficial area of the legs and reduces the number of stay bolts necessary to be removed from the side sheets in securing said ends in said side sheets.

It is apparent that the arch in conjunction with the elements divides the upper portion of the firebox in three laterally spaced passageways, namely two main lateral passageways 4645 and a secondary central passageway 41 of smaller area as defined by the spaces between said outlet legs of the various elements. With such an arrangernent, the products of combustion in their flow through the said passageways have a more intimate engagement with the entire surfaces of the outlet legsof the various elements. For instance with the products of combustion flowing through the various passages, there is no blind space at the front side of the outlet legs as would be the case should the central passageway be omitted, and which blind space would produce a vacuous condition at the front of each outlet portion of the elements. Such blind spaces are objectionable as they tend to disturb draft action through eddies transversely of the firebox. With the present structure the products of combustion flowing through the spaces 4641 follow around the outer surfaces, of the legs 36 so as not only to avoid eddies which disturb draft action but so that the water in said legs absorbs more heat units to give a better water circulating and steaming action.

Again, because the products of combustion do flow around and in relatively intimate relation to all parts of the element, the temperature on both sides of the elemenLis more nearly equalized and stresses which would be imposed by diflerences in temperatures are minimized.

The element 34 in the combustion chamber is the same in construction as that before described, the only substantial diflerence being that it has legs of shorter length than those before mentioned and the parts of this element are indicated by the same reference numerals as hereto-" fore used. It is pointed out that certain relative movement occurs between the sheets of the firebox and which movement is due to stresses developed in temperature changes. Circulating elements of the structure described herein arerelatively flexible so as to yield to and accommodate such movement without the production of scam cracks or fractures either in parts of the elements themselves or in the sheets of the firebox or in the welds which secure the legs of the elements in said sheets of the firebox.

In operation, colder water, from the side water legs, is drawn in through the inlet legs as two streams which meet at the junction-like mid portion 31 to pass out through the outlet legs into the water space above the firebox. Thus, a large volume of water is constantly flowing over the central bottom juncture point and aiding in keeping the surfaces clean. When the two inlet streams meet at said junction-like mid portion, there is also some turbulence which assists in washing the internal surfaces of the elements at this point. Thus, no sediment can accumulate in the element so that burning out of the element is substantially, if not entirely eliminated.

In the claims, the term side sheets is intended to include not only the side sheets of the firebox proper, but also the sheets at the sides of the combustion chamber. The term firebox is also to be construed as including the combustion chamber.

While in' describing the invention I have referred in detail to the form, arrangement and construction of the various parts thereof, the

same is to be considered only in the illustrative sense so that I do not wish to be limited thereto except as, may be specifically pointed out in the appended claims.

I claim as my invention:

1. In combination with a locomotive boiler firebox including a crown sheet and side sheets, a water steaming and circulating element in the firebox comprising an upwardly arched lower tubular-like portion extending transversely of the firebox and having ends opening through the side sheets and a plurality of spaced upper tubular portions, the top end of each of which opens separately through the crownlsheet and the bottom ends of which have a common inlet that is is communication with said lower portion. 2. As an article of manufacture, a water circulating and steaming element for a locomotive boiler firebox made from a pair of similarly shaped parts secured in pressure-tight engagement edge to edge and providing a plurality of downwardly and' outwardly diverging tubular portions forming an arch-like structure adapted to extend transversely of the firebox with its ends opening through the side sheet of the firebox and also providing a plurality of spaced substantially tubular portions adapted to be disposed in a generally upright position and each having an end adapted to extend through the crown sheet so as to connect said downwardly and outwardly extending tubular portions with the boiler water spaceabove the crown sheetthe bottom ends of the uprightly disposed tubular portions having a common inlet that is in communication with the outwardly diverging tubular portions.

3. In combination with a locomotive boiler firebox including a crown sheet and side sheets, a plurality of. longitudinally spaced transversely extending water steaming and circulating elements in a firebox, each element comprising an upwardly arched tubular-like lower portion having ends opening through the side sheets and a plurality of spaced upper tubular portions each opening separately through the crown sheet and connecting said lower portion with the boiler water space above the crown sheet, said lower and upper portions coacting to provide at least three longitudinal spaces in the upper portion of the firebox, each topped by the crown sheet, for

the passage of the products of combustion toward the tront end of the firebox said upper tubular portions having a common inlet that is in com-' municatlon with said tubular-like lower portion.

4. In combination with a loco'motive boiler firebox including a crown sheet and side sheets, a plurality of longitudinally spaced transversely extending water steaming and circulating elements in a firebox, each element comprising a tubularlike lower portion having downwardly extending ends opening through the side sheets and a plurality of spaced apart upper tubular portions, each opening separately through the crown sheet and connecting said lower -portion with the boiler water space above the crown sheet, brick supported by at least certain of said .elements and providing an arch in said firebox, said upper portions cooperating with the arch in providing at least three longitudinal spaces above the arch for thepassage of the products of combustion toward the front end of-the firebox said upper tubular portions having a common inlet, that is in communication with said tubular-like lower opposed tubular legs extending outwardly and downwardly at least in part to provide an archlikestructure adapted for arrangement trans versely of the firebox with the ends of said less opening through the side sheets thereof and ineluding at least two laterally spaced, upwardly extending tubular legs, the top end of each leg be-' ing adapted for engagement in and to open thereof through a common inletf 6. -As an article of manufacture, a water steaming and circulating element for a locomotive boiler firebox comprising at least a pair of opposed tubular legs extending outwardly and downwardly at least in part to provide an arch-. like structure adapted for arrangement transversely of the firebox with the ends of said legs opening. through the side sheets thereof andineluding at least two laterally spaced, upvhrdly, extending tubular legs, the top endof each leg being adapted for engagement in and to open through the crown sheet, and the bottom ends of which extend inwardly and join each other as well as joining with said first mentioned pair of 1688 GUST J. CHRISTENSON.

DISCLAIMER 2,151,009.-Gust J. Christenson, Chicago, Ill. LOCOMOTIVE BOILER FIREBOX 'scl Patent dated March 21, 1939. aimer filed August 28, 1940, by thd assignee, Locomotive Firebox Company.

Hereby enters this disclaimer to claim 1 in said Letters Patent.

[Oflicz'al Gazette September 24, 1940.] 

